Sugar-crystallizer.



No. 759,686. PATBNTBD MAYIO, 1904.

G. ENGEL. V SUGAR GRYSTALLIZBR.

APPLICATION FILED my 1. 1901. no menu. a 5EBETB-B}I BBT'1.

J WITNESSES: INVENTOR No. 759,686. PATENTED MAY 10, 1904.

G. ENGBL,

SUGAR GRYSTALLIZER.

APPLICATION TILED MAY 1. 1901.

H0 MODEL. 3 SHEETS-SHEET 2.

llllllllllll] {IIIIIIIIIIIII llzpeniar.

i/im w,

"n4: uonms PETERS ca, PHOYO-LITHO, wmmuamu. n. c.

UNITED STATES I Patented May 10, 1904.

GODFREY ENGEL, OF BALTIMORE, MARYLAND.

SUGAR-CRYSTALLIZER.

SPECIFICATION forming part of Letters Patent No. 759,686, dated May 10, 1904.

Application filed May 1, 1901. Serial No. 58,276. (No model.) i

T0 at whom it nuty concern.-

Be it known that I, GODFREY ENGEL, a citizen of the United States, residing at Baltimore,

State of Maryland, have invented certain new My invention consists in the novel means employed for heating or cooling the contents of the crystallizer and for setting up circulation of the fluid therein and in the novel manner of closing the stirring-arms and connecting the stirring-blades thereto.

The objects of my invention are to improve the construction of crystallizers to render the same more efficient, to produce effective circulation of the contents of the crystallizer by the action of the revolving stiri'ingerms, and to simplify and cheapen the construction of the crystallizer. These objects are attained in the invention herein described, and illustrated in the drawings which accompany and form a part of this specification, in which the same reference-numerals indicate the same or corresponding parts, and in which Figure 1 is a central vertical section of one form of crystallizer constructed in accordance with my invention, the stirring-blades being arranged in the form of spirals, so as to produce endwise circulation of the contents of the crystallizer. Fig. 2 is a corresponding view of another form of crystallizer, in which the stirring-blades are not arranged in the form of a spiral. Fig. 3 is an end view of the crys-' tallizer, showing the driving mechanism. Fig. 4C is a transverse section of the hollow shaft and a side view of two of the stirring-arms, showing how said arms are closed at their ends and showing how the stirring-blades are attached to said arms; and Fig. 5 is a longitudinal section of a portion of the hollow shaft, likewise showing how the stirring-arms are closed at the ends and how the stirring-blades are connected to said arms.

In the drawings, 1 indicates a chamber,

formed of boiler-plate or othersuitable material and preferably cylindrical in shape. It is provided with suitable manholes, through which crystallized sugar may be removed and through which workmen may enter when nec essary, and with a supply-pipe 2, a dischargepipe 3, and a hollow stirrer-shaft i, having hearings in the ends of the chamber and provided with stufling-boxes at its ends to permit the connection to it of pipes 5 and 6, through which hot or cold fluid or vapor may be admitted to its interior and circulated through it. Upon shaft 1 there is also a worm-wheel 7, intermeshin with a worm 8 (indicated in dotted lines in Fig. 3) upon a shaft 9, carrying beltwheels by which said shaft, and therefore the shaft 1, maybe driven.

a The shaft 4 is provided with a plurality of projecting stirring-arms 10. These arms are preferably formed of pipe, are screw-threaded at one end to permit them to be connected to shaft 4:, and at the other end are closedby flattening and welding togethertheir sides, all as shown in Figs. 4 and The flattening and welding together of the sides of these tubes not only closes their ends securely, but the flattened portion so formed makes an excellent seat for the stirring-blades to be connected to such arms.

11 11 in Fig. 1 and 11 11 in Figs. 2, 1, and 5 indicate the stirring -blades. When it is desired to produce circulatian of the fluid from one end of the vessel to the other, the arms 10 may be arranged upon the shaft t in spirals, the blades 11 then becoming spiral stirring-blades, as shown in Fig. 1, which not only agitate the contents of the crystallizer, but produce endwise circulation, acting in this respect like propeller-blades; but when such endwise circulation is not necessary the arms and stirring-blades may be arranged as shown in Fig. 2.

Since the arms 10 are hollow and are in communieation with the interior of ,the hollow shaft 4:, through which, as already stated, hot or cold fluid or vapor may be circulated, they form heating or cooling arms, as the case may be, transmitting heat to or conducting heat from the contents of the erystallizer, and

therefore serving to regulate the crystallization of the sugar from the QllJl31OIL Because these arms are constantlylnoving through the fluid in the evaporator they are very efficient in heating or cooling such fluid, heating or cooling all parts alike. The number of stirring-arms may be varied as desired and may be less or greater than the number shown in the accompanying drawings.

In the extraction of sugar the sugar-bearing solutions are evaporated in vacuum-pans, and the sugar is thereby caused to crystallize out of the solution until, because of the low sugar content of the solution or the presence of impurities, the sugar will no longer crystallize in the vacuum-pans. The solution is then passed into crystallizers, which may be divided into one or more groups according to the quality of the product to be'obtained. In these crystallizers the crystallization of the sugar is continued under conditions of temperature and viscosity produced by the operation of the crystallizers.

If conditions permit, sugar crystallizes at the point of saturation of the solution. The object of stirring the solution and of heating or cooling it, as the case may be, is to produce the desired favorable conditions.

If the sugar solution treated be a relatively high testing solution, the sugar tends to crystallize relatively rapidly in the crystallizer, and the solution should be cooled more rapidly than will be accomplished by simple radiation of heat through the walls of the crystallizer to the surrounding atmosphere. When such solutions are treated, therefore, a coolingfiuid, such as cold water, should be circulated through the pipe 4 and stirring-arms. 'Instead of cold water a brine solution, kept cold by ice or by the operation of a refrigeratingmachine, may be used or ammonia or other suitable gas under pressure may be expanded in the shaft 4 and stirring-arms.

If the solution treated be a relatively low testing solution, the sugar crystals form more slowly, and it is necessary to cause the solution to cool somewhat more slowly than would be accomplished by radiation to the surrounding atmosphere. Hot water or steam may be circulated through the pipe or shaft 4 and stirring-arms in such case.

My improved crystallizer may also be employed as an evaporator or drier for the treatment of many substances.

Having thus completely described my invention, what I claim, and desire to secure by Letters Patent, is

1. In an apparatus of the class described, the combination, with a suitable chamber, of a hollow stirrer-shaft therein, provided with means by which fluid or vapor may be admitted to it, and provided likewise with projecting pipe-arms, communicating with the interior of the stirrer-shaft, and therefore adapted to receive the heating or cooling fluid or vapor within said shaft, said arms being flattened and having their sides welded together, at their outer ends, whereby said arms are closed and seats are formed for a stirrer-blade, a stirrer-blade secured to the flattened portions of said arms, and means for rotating the stirrer-shaft.

2. In an apparatus of the class described, the combination, with a suitable chamber, of a hollow stirrer-shaft therein, provided with means by which fluid or vapor may be admitted to it, and provided likewise with projecting pipearms,arranged spirally about said shaft and communicating with the interior thereof, adapted to receive the heating or cooling fluid or vapor within said shaft.

In testimony whereof I aflix my signature in the presence of two witnesses.

GODFREY ENGEL. 

